A number of input devices are known for operating a graphic user interface (GUI) of a computer or (as implied in the following) of other devices that can be controlled by a GUI, primarily the so-called mouse which has established itself as a standard. Signals are generated by moving the mouse over a flat surface and are transmitted to the computer to be controlled, generating on the display a corresponding two-dimensional motion of the mouse pointer. For example, graphic control elements can be selected, activated, “held” in place, moved, etc., on the display with the mouse button(s) in a conventional manner.
Various other input devices are also known which have equal control functionality and compatibility to that of a the mouse, but operate differently. Examples are so-called trackballs, touchpads and joysticks. These input devices are implicitly included when referring hereinafter to a mouse.
So-called hardware controllers are now widely used in the area of computer-based digital audio studios. These hardware controllers control the corresponding audio software preferably via a MIDI interface and are in most cases specifically matched to that interface. Typical hardware control elements are here touch keys, rotary controllers and (motorized) slide controllers. In particular, rotary controllers have a significant advantages over a mouse for achieving continuous control, so that these are ubiquitous, for example, in mixers of computer-based audio studios. A manually generated rotation by moving a finger provides a significantly better sensory-haptic and fine-motor control of the controller than moving a mouse under the control of a person's arm motion.
The German published patent application DE 102 45 333 A1 describes an input device with a rotary controller. The input device includes a first control unit for moving a monitor, such as a cursor, on a display and a second control unit for changing parameters for controlling additional programs. In particular, both control units generate different signals, because operating the first control unit positions a marker on the display, whereas operating the second control unit does not change the position of the marker, but changes other input parameters—for example station frequencies of a car radio. Within the context of the solution described in the German published application DE 102 45 333 A1, actuating the second control unit must not produce a motion of the marker on the display, because the parameters to be changed are selected by moving the marker on the display to a defined position of the GUI. Changing the position of the marker during the operation of the second control unit may therefore cause the marker to be moved to a position of the GUI which is provided for changing a different parameter. As a result, the second parameter would then be (unintentionally) changed. In this solution, too, the control unit is adapted specifically for the application program, for example the control software of the car radio.
Also known is a scroll wheel (frequently provided as an operational control in addition to a mouse), where a thumbwheel without a limit stop preferably controls the scroll bars of a program having suitable software directly and independent of the position of the mouse pointer, as long as the corresponding program window is active.
Also known are devices with a rotary controller without a limit stop, which are connected with a computer and which use suitably configured driver software to control different parameters (e.g., the audio volume of a media player). However, the software to be controlled must support these devices. The number of parameters that can be controlled in this manner is limited in practice and the association of the parameters to be controlled with the device is rather indirect and complex.
Disadvantageously, the aforedescribed solutions either lack the rotary controller which is ergonomically advantageous as a control element for precise control of the parameters, or the programs or devices to be controlled are inflexible and depend specifically on the input devices. The conventional rotary controllers are therefore not suited for controlling anything else but the specifically adapted programs, in particular not for controlling programs which only permit parameters to be entered via a GUI by using input devices, such as a mouse, touchpad and the like.
Such programs can be controlled, for example, by showing on the GUI a slider or another graphic object which are selected in a first step by moving the cursor positioned on the GUI with the mouse over the control button of the virtual slider or over the graphic object. In a second step, the control button or graphic object are typically “held” in position by pressing and holding a mouse button (frequently the so-called “left mouse button” which will be referred to hereinafter as main selection button which is used to generate the so-called main selection signals by pressing, holding and releasing this left mouse button). In a third step, the control button or graphic object is moved by moving the mouse, and in a fourth step the control button or the graphic object is again “released”. To precisely operate the virtual controller and to precisely move the graphic object, it would also be desirable for such programs to use a rotary controller instead of the conventional, but imprecise input devices, namely mouse, trackball, touchpad, joy stick, etc.